Epsilon Archive for Student Projects

Abstract

Cassava (Manihot esculenta Crantz) is a tropical root crop grown for its starchy
tuberous roots. In Vietnam, cassava’s use as a raw product for the starch and ethanol
industry led to its increasing importance. Also, Vietnam is one of the countries
predicted to be most affected by climate change and cassava may be one important crop
for securing agricultural production. These diverse needs highlight the necessity for a
diverse gene pool for different breeding goals. The genetic diversity of cassava on
farmers’ fields in Northern and Central Vietnam was explored by using an
interdisciplinary approach combining farmer interviews and genetic marker analysis.
The study also included eight Vietnamese accessions from the cassava Germplasm
Bank at CIAT, Colombia.
Cassava varieties on fifteen farms in Northern and Central Vietnam showed
high genetic diversity among varieties. Vietnamese farmers cultivated clones of
different varieties to a great extent, which they were able to distinguish based on
different morphological traits. However, genetic variation was also detected in some
cassava varieties grown in a single field. Farmers were able to conserve their varieties
as clones over long periods of time. Local and improved varieties were grown in both
regions. These two groups of cassava were genetically differentiated, showing the
necessity of preserving local varieties for increasing the gene pool for breeding.
Genetic diversity in the farmers’ fields was not covered by the CIAT accessions,
suggesting that local varieties should be incorporated into the germplasm bank.
This interdisciplinary study made it possible to detect the actual genetic
structure and diversity within farmers’ fields and it enhances the importance of
understanding the farmers’ influence on the genetic composition of cassava.